Tension and take-up device



W. D. 'KELLOGG ETAL.

TENSION AND TAKE-UP DEvIcEs June 17, 1941 Filed Sept; 28, 1939 MEET Patented 4 June 17,

UNITED STATES PATENT OFFICE! a 2.24amt TENSIQN AND mas-Ur DEVICE William Kello' gg'and John Fradenbilr'gh, Amsterdam. N. Y., assignors to Collins Loom Works, Inc., Amsterdam New York N. in, a corporation of Application September 28, 1939, Serial No. 296,960

meter of the wound roll increases. Such ad- .lustment by hand of the size of the weight is necessarily slow and it cannot be satisfactorily carried on in apparatus used with machines producing fabric at high speed the cost of production and. in addition, the inimpair the quality of the latter.

evitable variations in the tension on the fabric Various devices have been proposedto overcome these dimculties, but each such device with which we-are familiar is complicated and exrope wound on a drum mounted on the roller and the other end of the rope is attached to the' drum. The drumis connected to the roller by a ratchet wheel and pawl connection so that as the rope is unwound from the drum by the descending weight, the roller is driven in one direction and thereby advances the fabric.

In such apparatus, the descending weight reaches the lower end of its path of travel at repeated intervals in winding up a roll of fabric and each time that this occurs, the weight must be restored to its'initial position. For this purpose, the'drum is provided with a handle by which it may be rotated in the proper direction to wind the rope, and during this operation, the

roller is held stationafi. The frequency with I which the operations of restoring the weight to its initial position occun depends on the size of the drum, the length of rope employed, and the speed with which the fabric is supplied.

The prior apparatus is objectionable in that during the restorations of the-weight to its initial position which must be made several times duringthe windingup of a roll of fabric, the fabric advancing roller is held stationary and the tension on the fabric being supplied is reduced. Such reduction lntension impairs the quality of the, fabric and causes stop marks to occur in the goods. The take-up device, therefore, does not advance the fabric under constant tension throughout the winding of a roll, as is desired.

In the apparatus described, ithas been com mon practice to wind the fabric into a roll on pensive to manufacture and operate when-employed with high speed fabric producing machines.

The present invention is. accordingly, directed to the provision of a novel apparatus for advanclng a fabric from its point of production and winding it into a roll, which lacks the obiectionable features of the prior devices. The

new apparatus is superior to the prior equipment in that it is fullyautomatic and requires no attention other than initial adjustment. Also it is cheaper to construct and easier to maintain inproper working order and it may be operated with complete satisfaction. in connection with machines producing fabric at high output rates.

' The apparatus of the invention includes a roller which contacts with the fabric and is retated to advance the fabric from its point 'of' supply and a second roller which rolls up the fabric received from the first roller. The advancing and tensioning roller is driven by means applying a constant and uniform torque thereto so that the fabric is subjected 'to constant and uniform tension between the roller and the sup-,

gr'essive increase in the diameter of the wound 7 roll.

the advancing roller, but this is objectionable,

For a better understanding of the principles of the invention, reference may be had to the accompanying drawing in which an embodiment of the invention suitable for use with a fabric pro-- ducing mechanism, such as a warp knitting ma-.

chine, is illustrated. In the drawing,

apparatus in side directed fromits point of productionover a stationary member, such as a rod II, and passes ing will be progressively decreased as the ditherefrom into contact with and partly around Also it increases a advancing roller l2 mounted on a shaft I3 supported for rotation in bearings mounted in suitable framemembers l4. The shaft is rotated in the proper direction to advance the fabric from its point of production, and to prevent slipping of the fabric relative to the surface of the roller, various expedients may be employed. For some fabrics, the roller may be provided with spikes which engage the fabric, while for others, which would be injured by such spikes, the surface of the roller is roughened or preferably covered with a composition tubing having a roughened surface. A covering of the latter type may consist of a tube made of a material known commercially as Phenolite provided with a special finish for the purpose.

From the advancing roller I2, the fabric passes to a take-up roller l5 mounted on a shaft it supported for rotation in bearings. in suitable frame members H. The take-up roller is rotated in the proper direction to cause it to wind up the fabric delivered to it by the advancing roller I2. Both rollers I2 and I5 are rotated by automatic devices which cause theroller If to advance the fabric at a uniform rate and at a constant tension and cause the roller I5 to wind up the fabric received from roller I2 without affecting the tension inthe fabric as it is produced.

The automatic devices for driving the rollers are of similar construction and will. be described in detail in connection with the device for driving the roller I2 mounted in the frame it. Similar reference characters, primed, are used to 1 designate corresponding parts for driving the roller I5 in the frame II. The automatic driving members I8, I9, the endless element is a chain. A weight 22 is connected to the chain to impart movement thereto and thereby rotate the members I8, I9 and the roller I2. For this purpose, the chain may be formed with a bight 23 which supports an idler roller 24. The roller 26 is mounted on a pin 25 secured to a plate 26 to which is attached a rod 21 on which the weight 22 is mounted, the rod being guided in its vertical movements by one or more brackets 28 attached to the frame-work of the machine. Also mounted on the pin 25 is a positioning element which may be a roller 29 engaging a track 30 formed by one surface of a member 3| attached to a pin 32 secured to a frame member l4.

The mounting of the weight described is such that it tends to lengthen the bight in the chain and thereby rotate members I8 and I9 and the roller l2. The member l9, however, is held against such rotation, so that the weight is effective only to rotate member I8 and roller I2. Since the roller has a frictional engagement with aasasea able with the teeth of the wheel is a drivingpawl 34 which is pivotally connected by a pin 35 to one arm 36 of a bell crank lever pivoted on the pin 20. A spring 31, secured at one end to the arm 36, bears at its other end against therear surface of the pawl and tends to force the pawl into engagement with the ratchet teeth.

The bell crank lever, to one arm of which the pawl 34 is connected, is continuously rocked and, for this purpose, the second arm 38 of the lever is connected by a link 39 to a crank t0 fast on a shaft il. This shaft rotates continuously throughout the operation of the machine, but the pawl 34 is kept out of contact with the ratchet wheel except during the periods when the weight is to be restored to its initial raised position. During the period that the weight is descending, the ratchet wheel is held against backward movement by a holding pawl, 42 mounted on a pin secured to one of the frame members I4 and held in contact with the surface of the ratchet wheel by a springdS connected at one end to the tail of the pawl and at the other to the frame member i 4. Since the ratchet wheel is connected to rotary member I9, the latter remains stationary as the weight moves down.

During the descent of, the weight, the driving pawl 34 is kept out of engagement with the ratchet wheel by means of a plate 44 which is pivotally mounted on the pin 20 and is formed at one end with a cam surface 45 which engages a cam follower roller 66 mounted on the free end of the pawl. The other end of the plate extends downward beyond the pin 20 and lies in engagement with one or the other of two stops 47, dd, mounted in extensions from the member 3i. Between its ends, the plate 44 is provided with an extension 49 carrying a pin to which is connected one end of a spring 50. The other end of the spring is secured to the end of a bar 5| attached to the plate 26 and projecting upwardly therefrom, When the weight is in elevated position, as illustrated, the spring 50 lies above the pin 20 on which the cam plate 44 is point of attachment of spring 50 to bar 5| will the fabric, the torque applied to the roller by the weight results in the application of tension to the fabric l0 issuing from the supply mechani smyand since the size of the weight is not have moved downward so that the axis of the "spring lies below the pin 20. When the spring thus passes across the axis of oscillation of the cam plate, it swings the plate on pin 20 to move the lower end of the plate from stop 41 to stop 48. In that movement, the cam surface of the plate passes out fromibeneath the cam follower roller 46 on the pawl 34 and the pawl is moved into engagement with the teeth of the ratchet wheel 33 by the action of spring 31.

In the illustration of the apparatus, the weight is commencing its downward travel and in this condition of the mechanism, therotary member I? is held against movement in one direction by stalled and operated at lower cost.

the stop pawl 42 engaging the teeth of the ratchet wheel 3!. The weight is, therefore, effective to i apply torque to the advancing roller l2 and as the roller is rotated, the bight of the chain lengthens. Also, during such descending movement, the cam plate 44 is effective to maintain the pawl ll in inoperative condition. When the descent of the weight causes the spring I! to pass the center of oscillation of cam plate 44, the cam plate is swung by the springto bring the pawl 34 into operation and the continuously oscillat-' ing bell crank 38 causes the pawl to rotate the ratchet 33 in a clockwise direction and thereby rotate .the member I! to take up the chain,

shorten the bight, and raise the weight. The raising operation continues until the spring l acts to swing the cam plate 44 into the position in which it. puts the pawl 34 .out of action. Throughout the descent of the weight and its restoration to its initial position, the weight is continuously applying torque to the roller 11 through the sprocket wheel II and shaft I3 and,

since the weight is not changed in size, the torque thus applied is constant and uniform and a constant and uniform tension is, accordingly, ap-

plied to the fabric i0 issuing from the producing machine.

The fabric being advanced by the roller I2 is wound on the take-up roller II, which may be andpreferably is rotated by mechanismsimilar to thatemployed for rotating the roller ii. For driving the roller I2, the weight used depends on the tension which it is desired to apply to the fabric and when similar mechanism is employed for rotating the roller II, the weight used need only be suflicient to cause the take-up roller to wind up the fabric smoothly. As the diameter of the wound roll increases, the size of the weight used for rotating the roller I5 is not changed, but the weight descends'rnore slowly and the mechanism operates less frequently to restore the weight to its initial position. The

tension and the fabric thus advanced is wound intoa roll of increasing diameter without effect on the tension in the fabric from its point of production to the advancing roller. The new apparatus may be utilized in connection with assassa v element trained about the members, a weight connected to the element and exerting a constant pull thereon which is transmitted to the roller through the rotary member connected therewith and is'efiective to rotate the roller,

the weight descending from an initial position in its operation, means for rotating the secondrotary member to move the element to restore the weight to its initial position, and automatically actuated means for controlling the operation of the rotating means.

,2. Apparatus for advancing and taking up a fabric which comprises a roller in contact with the fabric, a pair of rotary members, one 0! which is connected to the roller, 9. flexible endless element trained about the members and formed with-a bight, a weight depending from the bight, means for advancing the second rotary member to shorten the bight and elevate the weight, said means including a ratchet wheel operatively connected to the rotary member and a continuously operating pawl engageable with the ratchet wheel, an element operable to control the action of the pawl on the ratchet wheel and movable between two positions, and a spring attached to the element and actuated by the weight upon a predeterminedmovement thereof to movev the element from one position to the other.

3. Apparatus for advancing and taking up a fabric which comprises a roller in contact with the fabric, a pair of rotary members, one of which is connected to the roller, a flexible endless element trained about the members and formed with a bight, a weight depending from the bigh't, means for advancing the second rotary member to shortenthe bight and elevate the weight, said means including a ratchet wheel operatively connected to the rotary member and a continuously operating pawl engaseable with the ratchet wheel, a pivoted cam member movable between two positions and effective in one position to disengage the pawl from the ratchet wheel, the cam member in its other position permittlng the pawl to act on the ratchet wheel,

and a spring connected to the cam member and to the weight, the axis of the spring being shifted by the weight in its movements to cause the spring to swing the cam member from one position to the other.

4. In a fabric producing machine having a fabric supplying mechanism, a roller for drawfabric producing machines of many types, of, which a warp knitting machine is only one example, but it is particularly suited for use with warp knitting machines operating at high speeds. The mechanism has been found to operate more satisfactorily than prior tension and take-up devices and since it is of simple coning the fabric from the supplying mechanism under tension and a second roller for windin up the fabric received fromthe first roller, and means for-driving one of the rollers including a sprocket wheel connected to the roller, a second sprocket wheel, a chain trained about the sprocket wheels and formed with a bight, and

a weight depending from the blght, the combination of a ratchet wheel connected to the second sprocket wheel, a continuously operating spring-pressed pawl engageable with the ratchet wheel to advance it to causevthe sprocket wheel to shorten the bight of the chain, a cam for engaging the pawl with and disengaging it from i the ratchet wheel, and a spring connectedto the tact with the fabric, means for driving one-roller to cause it to-advance the fabric, and means for driving the other, roller to cause it to roll up the fabric delivered to it by the first roller, the driv-' ing means for, each' roller including a pair' of rotary members, one of which is connectettto the roller to rotate therewith, a flexible endless weight and operable when the weight-reaches predetermined paints in its path of travel to act on the corn to cause it to perform its functions. 5.11: a fabric producing machine having a fabric supplying mechanism, the combination of a roller for advaneing'the fabric from the'supplying mechanism. a second roller forwinding up the fabric received from the first roller, and

means for driving one of the rollers including a sprocket wheel connected to the roller, a sec-' ond sprocket wheel, avchain trained about the sprocket wheels and formed with a bight, a weight depending from the bight of the chain, a ratchet wheel connected to the second sprocket wheel, a pawl for holding the ratchet wheel against retrograde movement, a driving pawl engageable with the ratchet .wheel to cause it to advance and rotate the second sprocket wheel to shorten the bight, an element movable between two positions and effective in its respec- 2,24e,aee 1 tive positions to disengage the driving pawl from the ratchet wheel and to permit said pawl to engage and drive the ratchet wheel, a connection between the movable element and the weight through which the weight operates upon reaching predetermined movements inits pathof travel to move the element from one position to the other, and means for actuating the driving pawl.

WILLIAM D. KELLOGG JOHN FRADENBURGH. 

